1. Field of Invention
The present invention relates to an optical component, and more particularly to a dustproof protective lens and its module for an LED road lamp.
2. Description of Related Arts
Conventional lighting lamps are gradually being replaced by energy-conserving and environment-friendly LED lighting lamps. However, by using an LED as a light source, a light redistributing is usually necessary because of the features of the LED itself. Usually the emission side of the LED is covered by an optical lens to meet lighting requirements of practical using. For example, in road lighting, the lighting distance along the road direction is relatively long while the lighting distance at the direction vertical to the road direction is relatively short. Besides, the exit surface of the optical lens adopted by the conventional LED road lamps is usually not flat, which causes that the exit surface tends to have dusts piled up thereon if used for a long time. Therefore, the light producing efficiency is greatly reduced. It is also not easy to modularize the conventional lens.